24 NOTES ON SABLE ISLAND—MACDONALD. 
station, and that vessels not bound for the Island, nor driven 
there by currents or stress of weather, would no more run for it 
than they do now,—that they would, in fact, keep clear of it, it 
having no harbour of refuge ; and that vessels outward bound 
would not require anew point of departure, while those homeward 
bound had all the coast before them; and if made to revolve 
E. and W., it would show in which direction the bars lie, and to 
government vessels it would be of great service. But, as before, 
no further action beyond debating the matter took place—at 
that time. 
Foremost among the dangers surrounding this Island is that 
arising from the irregularity of the marine currents that sweep 
its shores, To trace the origin of which let us turn our atten- 
tion for a while to the course of the gulf stream and polar current. 
By glancing at Maury’s Physical Chart, it will be seen that 
the gulf stream, after discharging its heated waters through the 
channel formed by the coast of Florida on the one side and Cuba 
and the Bahamas on the other, follows the trend of the American 
coast northward until approaching the shoals of Nantucket, 
where it swerves to the N. E., passing south of Sable Island to 
the tail of the great bank of Newisundland: and then str etching 
over to Europe in a due east direction. 
In opposition to this, we have the cold, ice-laden current of 
the North, one portion of which, after leaving the Arctic ocean, 
passes southward along the eastern coast of Greenland,where being 
joined by another branch coming from Baffin’s Bay and Davis’ 
Straits, it passes along the coasts of Labrador and Newfoundland 
to the great banks, where it is met by the northern edge of the 
gulf stream, At this point a-division of the polar current takes 
place,—one portion, from its greater density, sinks below the 
warm current of the gulf stream and continues its course south- 
ward as a sub-marine current. This has been doubted. In the 
Transactions of this Institute for 1865, is a letter from Admiral 
MILNE to the President of this Society, concerning the currents 
on the N. E. coast of North America, in which he says: “This 
polar current passes along the east coast of Newfoundland as 
far as Cape Race, where a western part runs round if into St, 
